Machine telephone switching system.



L. POLINKOWSKY, MACHINE TELEPHONE SWITCHING SYSTEM APPLICATION F1150 111111.55. 1914.

f 1,160,447. m6111611 Nov. 15, 1915.

fly. 2M m JR-32:06 Lg/ 31 @NME STAES LIPA POLINKOWSKY, or BRUSSELS, BELGIUM, AssIeNoa rro COMPANY, orNnw YORK, N. Y.,

, WESTERN ELECTRIC 'A CORPORATION 0F ILLINOIS.

MACHINE TELEPHONE sWrrcHING SYSTEM.

ing telephone exchange systems and more particularly to improvements in systems iny which an automatically operating switch searches for and seizes an idle one of a plurality of circuits or Sets of circuits.

One of the features of theinventionfprovides'such an arrangement of circuits and apparatus that the switch which operates to search for and seize an idle circuit or sets ot circuits from a plurality of circuits or sets of circuits, may be of simple and ecient design operatingat high speed land producing positive contact between the circuit to be extended and the circuit or circuits seized.

A. more] specic feature of the invention ,relates to the arrangement vof circuits and apparatus whereby an automatically operating power driven switch which may beoi` the type known to the art as asequence switch may be used to extend a. single circuit or set of circuits to an idle one of a group of circuits or sets of circuits `to which such switch has access, such arrangement of circuits and. apparatus involving particularly thel test circuit by which such sequence .switch is controlled and the relation of such test circuit, and particularly of thecontacts of such sequence switch forming a part thereof, with the circuits under test and the contacts of such sequenceswitch adapted to VVform a part of a selected circuit when seized.

Other novel features will vsufficiently appear from a description of the embodiment of the invention shown in the drawings, in which Figure 1 shows the invention as'embodied in a machine switching telephone system in which a connecting circuit islto have associated therewith one of a plurality of registering and controlling equipments for the `purpose of extending the connection desired over Such connecting circuit. Fig. 2 is `a graphic representation of the time relation of the closure of certain of the sequence switch contacts shown in Fig. 1. In the drawings. G00 represents a sequence Specification of Letters Patent.

Patented N ov. 16, 1915.

Application filed March 5. 1914. Serial No. 822,589.

switch associated with the connecting circuit referred to. All of the sequence switch contacts indicated above theupper dotted line of Fig. 1 are either directly controlled by the sequence switch 600, Such as sequence switch springs 601, 604, 607, 613, 616, and 617, or are associated with some other sequence switch in turn associated with the same connecting circuit, and may be indirectly controlled by Such sequence switch 600, as `for example, the sequence switch springs 206 and 210. On the other hand the sequence switch springs 401, 406 and 405 shown below the lower dotted line of Fig. 1 form apart of a sequence switch 400 associated with one of the registering and controlling equipments to which the connecting circuits referred to has access.

Between thek dotted Llines of Fig. 1 is showna sequence switch 700 which is adapted to search for and seize an idle registering and controlling equipment. All of the sequence switch contacts indicated between the two dotted lines are associated with such sequence switch 700. The positions of the sequence switch springs of this sequence switch are closed as shown in the usual manl by theV numerals adjacent to such springs; `for example, the spring 704 is closed in position 2 to its bottom contact; the samespring is closed in position 5 to its top contact, such spring being closed to either of itsk contacts only in the positions noted.

On the other hand the springs 701 and 703 ated with that equipment to which the leads 11, 12, 13, 14 will be connectedA when thesequence switch 700 stands in its second position. It will be understood of course that there may be another equipmentfor each of the other positions of the sequence switch to which the leads 11,12, 13, 14V will be connected when such sequence switch 700 stands in suchrother positions. In the embodiment shown the sequence switch 700`is indicatedv as being provided with siX positions, and

the leads of Yfive other registering and controllingy equipments, thanthe one 13o-which*V the leads 21, 22, 2,3, 24 are individual, are

400 of such equipment out of its Vnormal pclsition,'thereby opening the direct circuit to battery, but substituting before such circuit is opened a circuit through the front contact of the relay 426, spring 406 and'resistance 451, which willbe suiiicient to maintain the relaysin the test circuit which has seized suchequipment, energized, but will not place sui'licient potential upon the 'contacts to fth position; and still another in its siXth Position.y c p l The lead connected to thee-springs 704,

" 7 05, 7 06 forms part of the test circuit of the sequence switch V700. Correspondingly the which thelead 25 is multiplied in the sequence switches 700 of the various co-nnect- ,jing circuits having access tosuch equipment to allow' the operation of the test'relays lead 25. is the'testlconductor individualto f the leadsofcach of the registering and conc, trolling equipments to which the sequence ,the registering and controlling yequipment indicated to whichfthesequence switch 700 The invention will be further best understood from a description ofthe operation sultof the receipt of this call the sequence switchy 600 has been brought into its second ,willconnect the Vleads Jfrom the connecting. Vcircuit inits second position.

thereof.v

At this point it should be observed that switch 7.00 has access, may be multiplied to sequence switches corresponding to the sequence'switch 700 of a whole group of connectingcircuits, and one yor more ofsuch .of theiembodiment thereof shown in the' registering and controlling equipments may be busy or idle at any given time, anyone of vsuch group of registering and controlling 'equipments f equally well serving for assoposition, as has alsothe sequence switch ccn-r Y.

trolling .the springsA 206Y and 21.0. second position of the sequenceswitch 600 a Acircuit lwil-l be established over theV back contact ofthe relay 240, spring .613, and spring 702 for the sequence switch 700. Under'the control of the spring 701 thesequence switch v700 can vonly come to-.rest-inV one of its definite positions as is usual in switches of this type. However, atthe time of the establishment of the circuit just traced no circuit could exist for the relays 240 and V235 evenl though the spring 604 is at that time closedon account of thefact that the spring703 is open in each definite orfstopping position of thesequence switch 7 00. VThe sequence switch 700 will therefore `start in motion, and-,inY this movement will test for anidle registering Vand controlling equipment o f the plurality of such .equipments to which it has access. 'The idle conxbeing applied to'such'lead by theclosure of VVthe spring 405, which spring is only closed when the registeringand controlling equipinentof which it forms a part is in its nori mal or idle position as indicated Vby the nur' 'ineral l` placed adjacent such spring 405 f .uponthe drawings. It will be observed that when the registering and Vcontrolling equipment indicated below the lower dotted line on Fig. `1 has been seized, therelayv 426 is energized, and drives the sequence" switch In. thev z ciation with any oneof a larger group'of connectingcircuits with each of which conquence switch 700. y

As has been above suchas the sequence switch described, the sequence -lswitch `700V shown on the drawings has been started in motion when the sequence switch 600' came into its second position. As the sequence switch 700 leavesthe position in which it now stands,r assuming, forexample,

"that it stands in its Nol` position, the

spring 701 thereof will be closed to insure ythemovenient of such sequence switch completelyinto itsfsecondposition. A deiinite v periodafter such sequence switch has started to move from' its first position, the `spring V70d top willbe opened'.Y It is only Vafter the opening of thespring 706 top as the sequence .switch 7 00 isfmoving from its first position .tliatthe spring 703 will be closedv and such spring '703furtherniore will be again opened f either before, ori simultaneously with, the opening of the spring 701 as the sequence 'switchv 700 is coming into its second position.

`ditiono-f one of such equipments -will be in- Furthermore as the sequence -switch 700 is coming into rits second position the spring V7044 bottonirwill be closed for `afdeiinite period before'the opening of the spring r703.

.it is during this period, in which the spring 703` and the .spring y704 bottom are both closed, that the test todetermine the busy or idle Vcondition of the register controlling equipment towhich the sequence switchl 700 kwill be connected in its second position, is

made. It' at this time this equipment is idle, 4 full battery potential will be foundrupon the contactv with which the spring 704 makes circuit on its l lower side. Such being the case, the relay 235 will receive suiiicient current through .its right-hand high resistance winding tocause the energization Aof such relay, andsuch relay, together with the relay 240 will he energized.- The energzation of the relay 235 establishes a low resistance path through its left winding and its own armature as well as through the relay 237, which so. reduces the potential upon the lead 25 that no, other sequence switchZOO testing for an idle rr*egistering and controlling equipment will ,be able to have its relays 235va7nd 241:0 energized at this time. The energization of the relay 2&0 opens the power circuit of the .sequence switch 700 and .substir tutes a direct ground connection through its armature and rontcontact vfor the ground connection of the test circuit which at this time existsr through the spring 703. The springs 701` and 703 iny the further movement of the sequence switch T00 now open as suoli sequence switch comes into its second position, and the sequence switch 7,00A will stop in such position. y

The energization of the relay 237 by the closure oi' the contact of the relay 2.3.5 closes a kcircuit over its kiront contacty and the spring 607 todrive the lsequence switch 600 yout of its second position. i Such sequence switch coming into and stopping in its third position opens the springs 604, 607 613,

and closes the springs ..616` and 617, and also indirectly closes the springs 206 and 210.

At the same time that the relay/(7235 wasV Y energized, the relay 426 was energized, and

drove the sequence switch 40,0 out of itsiirst position, opening the spring L1;()5 and closing the spring 406. This so reduces the potential upon the contacts in the sequenceswitches-700tol which the lead 250i the seized equipment is multiplied,thatthe leads to this equipment may noty be connected to or seized by any other connecting circuitk even though the spring 604 is now open. The closure, however, of the springs 206, 210, 616 and G17k connects the .four leads 11-2l, 12-22,l3-23, 14-.24 through from the connecting circuit to theseized registering and controlling equipment.

In the casev assumed, however, if the equipment to which` the leads of the sequence switch 70.0 will be'connected in its second position was busy las the sequence switch 700 came into its second position, the relays 235 and 240 would not have been energized, and when the springy 701 was opened as the sequence switchf700 came into the second position, power would still be supplied to such sequence switch over the back contact of the relay 240 and the spring 613,y and the sequence switch 7,00 would continue to move through its second position and into its third position. On leaving its second position the spring 70.1 would again be closed.

In this movement aftery the spring `704, bot-k tom` is opened, ,the spring, 7.03: would be 'closedfand forr adenite period before'thc opening of the Springs 701 and,L 7,03 'the' spring T05 topV would be closed. In .the period after the closure 0f the Spring 705 top, and before the opening of thespring. y (03 a test would be made of the busy or idle conditionk of the registering and controlling i equipment to whichthe leads, of the sequence switch 0 0-y lwoulyflbve closed in its third position precisely as was the condition of jthe-V registering and controlling equipment *t0 which the sequence switch 4;.00 shown isindividual was tested as the sequence switch 700 was coming into its second position. If at, this time the third registering and control ling ejqupinent` (that is, the one t0V which the sequence switch 700 makes connection in its third position) `is idle, the relays2`35 and 24;() willbe energized kas has already been described, causing the sequence switch 7 0() to stop inits third position, and extend connection to smh-third equipment, the sequence lswitch 60.0 beingatthe same ytime moved into its third position to complete the circuit of the leads extending from the connecting cir-Vy cuit to such third equipment. On the other hand' if the third equipment was busy at this time, the sequence switch 700 would be continued in motion through its third position bv the. maintained closure of the circuit including'the back contact of the relay 240 c and the spring 613, and it would continue in motion `to its fourth position inisuch move- 'ment testing inta corresponding manner the busy or idle condition of the fourth equip- 00 ment to whichsuch sequence switchlOO has access.v u.

The utilitvot the spring O3 and the particular timed relation between the closure of suchspring and the closure of the springs llios 7,01, T04, y705 .and 70,6` will ,be apparent if it is assumed that as the sequence switch 700, Y having tested the second equipment as it wascoming into the second position, is moving'out of such second position, and the spring ilo Ol is again, Closed, Such second equipment yShQuld become idle beforethe spring 704 busy, andfconfusion would obviously result 11,25

dueto the connection of two connecting cir cuits to the same registering and1 controllinf5v eaupiiient A more. probable diiculty, however, would arise from thefact` thaty the relay 23@ having, oec@ been energized, .the e30 f sequence` switc'hr600'has left its ysecondpo'si- Y l Vtion vandi-come intoitsthird position as a 1 result of which the springs 206, 210, 216, and 217 areclosed If the third registering and "controlling equipment is busy, theclosufre the fourth erqlllment is also busy,` as thesejquence` switch 7 00 passed through its fourth vrposition, the closure of the springs 206, 210, f 216, and 217 would also detrinientally affect the operationv of suc'hfou'rth registering and controlling equipment; Tovpreveiit this interference with equipments already in use,

the spring 703 is arranged so that 'it is not Vclosed until after the spring'701`, 705, 7 06;topy or bottom, is' opened as the sequence switch f A Away lbetween such two positions has been 7 00 leaves thel position inwliich such spring is respectively closed. Thisrelation between the several springs is" plainly set forth in Figr2 ofthe drawings. 1t; will" be observed from this figure that spring 706 top is closed v in* position 1 (the vertical lines of 'this' figureV c "representing the stopping positions of the sequence Vswitch 7 00 as'indic'ated by-the nuvine'ral at'theftop respectively 'of such lines).

Imposition 1, furthermore,-'Ythel spring 701 andthe spring 703are'both open.

As the 'sequence switch 700 starts from its Y first position, the 'spring 701 is closed to insiire'i'ts complete' movement into itssecond position. Shortly before the sequencev switch 700 comes to a position midway: between its Y 4first and second position, the spring v706 top opened. After the spring 706 is KVopened, thei'spiingl 703 'is'closed' vShortly after the sequence switch 700 has passed ythe point midwayzbetween its first and second positions, the spring 704 bottom pis closed. At this timethe spring 7 01, 7 03 and 7 01 bot- 'tom areall closed, and the testV ofthe second equipment-,stakes place. After-a definite further' movement of the sequence switch 700, Vthefspringj703 Vis again Vop'eneoh'and shortly thereafter, or simultaneouslythere- `with, thefspri'ng 701`is openedfthe opening of thespring'701 taking place a sufficient Y p'eriodbefore'the sequence switch 00v comes into its lpsecond position to insurethat such sequence switch does" not 'run through its second position'of its own momentumeven `though the 'power circuitxthereof is at `that time opened.v In' the second position Aof the sequencetjswitch, b'othpthey springs 701-and A703 are' 1openedbut the spring 704: is closed'.A

"Correspondingly in the movementfof the sequence* switchz'0 from itssecondftogitsy `third"position they spring 704 Vbottoinvis closed untilV shortly 'before-j the sequence f Y switch'comes to a point midway `betweenits second Vand third positions. vOn the other v hand,"shortly after the sequence switch left and furthermore after the sequence switch 700 has passedthe'point midway between v. its second and third positions, the spring 705 top isclos'ed. Asthe' springs 701 and 703 are not again opened in this movement'until shortlv vbefore the sequence switch comes into'its third position, there is agdefinite period during which the springs 705 ton and i703 are both closed. T his period is sufficient for the testing of the third eouipmeiit to 'which the sequence switch700 has access.

It will be observed, therefore, from Fig, 2, that as the spring 70 is` never closed in the movement of the sequence switch 7 00y from one position to thefnext until the' point'inidreached, nor falsetest can kbe made due to the c idle condition of the eouipmentlindividual v-to the position ofthe sequence switch 700 from which such sequence switch vis moving. Furthermore VVas the spring 703 is openedin vthe movement ofythe sequence switch 700 from one position to the next not later than lthe spring 701Lis opened, itj is impossible forl the relays 235 `and5240 to'be energized after thespring 7 01 has been' opened Ydue tothe 4"equipment individual to the V position iin n: which the sequencel switch'700 is nowmovingtbec'omingidle'so late in such movement that theseouence switch 700 will Vnot be able to stop' in the position individual to Vsuchy equipment: 'that is to say, if'the rspring 703k :were not opened before,rv or simultaneously with, theV spring 701, it might 'be that the relays 235 and240 which latter relay mainytainsthe power 'circiiit for the,V sequence lswitch 700 after the lspringr701 is opened) would ybe energized to open the power circuit for such sequence switch 7 00 so late that such sequence switch would pass through 'the position into which it iscoming of its own momentum, and would again close the spring 701, which closure would cause-the ich sequence switchv 7 00 to Vcontinue on into its n next position'in spite ofthefact that the ref-la'ys235, 240 and 24L7Yhavingrbeen once en fer'gi'zed the sequence switch 600 has been driven'froniits secondiiiosition.`

- VAs has been labovedescribed, the nio've-V ,ment of theseqiience `switch600froin itssec? ond position before ,an idle equipment has been yproperly Y seized would ycause disturbancev in any busvi'efiuipments the contacts of whichmay be closed in the further move- "ment of the sequence'switoh 700 vseeking an idle'equipment. i L It will be apparent, therefore, thatl in the embodiment of the invention shown in Fig.

'1 nol false test cantake place, andV no interference' with busy equipments will result Veven though the sequence switch 700 in its searching operation closes its springs to the leads, such as 21, 22, 28, 24, individual to such equipments.

While there is shown herein a particular embodiment of the invention, it will be of course understood that the invention is not limited to the specific function or apparatus shown, but may be utilized in any c1rcumstances where the selection of an idle circuit or set of circuits from a plurality of circuits or sets of circuits is desired by means of a simple, positive operating, automatic switch, and may be modified in many ways while still retaining the characteristic features of the invention.

I claim l. An automatic selecting switch, a plurality of circuits terminating in said switch, test contacts for said circuits, a test circuit associated with said switch for testing the busy or idle condition of the circuits terminating in said switch as indicated on the testcontacts individualk to such circuits, and contacts included in said test circuit controlled by said switch, such contacts being closed only during a definite portion of the movement of such switch from one of its positions in which connection is made to One of said plurality of circuits to its next such position.

2. An automatic selecting switch, a plurality of circuits terminating in said switch, test contacts for said circuits, a test circuit associated withrsaid switch for testing the busy or idle condition of the circuits terminating in said switch as indicated on the test contacts individual to said circuits, and contacts included in said test circuit con trolled by said switch and closed by said switch in its movement from one position in which connection is made to one of said plurality of circuits to its next such position only after the contact of such test circuit with the test contact of the circuit individual to the position from which such switch is moving has been opened, and main tained closed thereafter for a delinite portion of the movement of such switch into such next position.

3. An automatic selecting switch, a plurality of circuits terminating in said switch, test contacts for said circuits, a test circuit associated with said switch for` testing the busy or idlecondition of the circuits terminating in said switch as indicated on the test contacts individual to said circuits, a magnet for moving said switch from one of its positions in which connection is made to one of said plurality of circuits to its next such position, a` local circuit for said magnet closed by said switch as it moves from one position and opened by such switch as it comes into its next position, and contacts included in said test circuit controlled by said switch and closed thereby only after such switch has opened contact with the circuit to which it is connected in the position from which it is moving, such contacts being opened by such switch when such local circuit is opened on coming into its next position.

4. An automaticr selecting switch, a plurality of circuits terminating in Said switch, test contacts for said circuits, a test circuit associated with said switch for testing the busy or idle condition of the circuits terminating in said switch as indicated on the test contacts individual to such circuits, contacts in such test circuit controlled by such switch, such switch closing such contacts in said test circuit and controlling the closure oi" suchtest circuit to the respective test contacts in such relation that said test circuit is complete only for a deiinite period while such switch is coming into position to make connection to one of such plurality of circuits.

In witness whereof, I hereunto subscribe my name this twentieth day of February, A. D. 1914.

LIPA POLINKOWSKY.

Witnesses:

F. T. yVooDWARD, H. TUCK SHERMAN.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. G. 

